Which of the following best describes the relationship between primary and secondary ambient air quality standards?

A) The primary standards must be met within three years of the creation of a state implementation plan, and the secondary standards must be met within a reasonable time.

B) The primary standards must be met within a year of their creation, and the secondary standards must be met as soon as economically feasible.

C) If the primary standards are met within three years of creation of a state implementation plan, then the secondary standards need not be met.

D) Both the primary and secondary standards must be met within five years of their creation.